I am about 5 weeks from having my 4th baby. We have always used an infant bucket seat, but have decided that this time it would be more cost effective to just buy 1 carseat that will last through all or at least most of the safety seat age/weight. What do you recommend? This seat will sit in a bucket seat of a minivan, so narrowness isn't a huge concern, but would be much more versatile if we wanted to shuffle seats around later. TIA!!!

There really isn't one that will do it all. There are some that will get you to booster age. Boosters are relatively cheap, though. I would suggest the Graco My Size/Size 4 Me or Graco My Ride. Also, the Radian does make a decent seat for an infant, but at a 45 degree angle, it will take up TONS of space. The Maxi Cosi Pria is also really nice and has an insert that will allow a newborn to sit at the right angle, but have the actual seat a bit more upright.
In short, these are the options, IMO:
Graco My Ride
Graco My Size 70/Size 4 Me/Headwise
Diono Radian R120 or RXT(technically, they turn into boosters, but are not a great booster)
Maxi Cosi Pria

Also add Britax convertibles (Roundabout 55, Marathon 70, Boulevard 70, Pavilion 70CS, Advocate 70CS) to the list. For small newbies you might need the infant positioning insert, which is sold separately.

The Evenflo Triumph 65 is a decent fit for average to large newborns as well.

One other thing - since you have older kids, the option of handing seats down can usually limit the number of seats you end up buying. It might be that your kids are old enough where the convertible seats you have bought in the past are expiring soon (or have already). But definitely something to keep in mind with boosters and any new seats that you end up buying in the next few years!

One other thing - since you have older kids, the option of handing seats down can usually limit the number of seats you end up buying. It might be that your kids are old enough where the convertible seats you have bought in the past are expiring soon (or have already). But definitely something to keep in mind with boosters and any new seats that you end up buying in the next few years!

Yes, I know. This would be the reason I don't have an infant bucket seat any longer... it expired Jan 13. We were in a car accident late last spring, so my 2 children that are in boosters have new ones. However, the one that I bought DD is VERY girly and I wouldn't pass it to my son even if it wasn't expired. But the high back booster that DS2 has would work for another boy, but it would be determined by the expiration date ultimately.

So, it would seem that what is currently available is good for infant and FF facing toddlers but won't necessarily work for the longer duration. Hmmm... wondering if I should just get the bucket seat then that is designed to hold up to a 2 yr old. And then buy a FF 5 pt harness booster that can convert to a seat belt booster... Any opinions?

If the Radian will fit at a 45* angle in our van (waiting for warmer temps to play with Levi's seat) we're planning to get another one for Hiccup. With an 8 year "lifespan", it'll definitely get us from birth, through ERF and FF, to booster age. They're $$ but worth it to not have to spend $200 each on a couple different seats, kwim?

So, it would seem that what is currently available is good for infant and FF facing toddlers but won't necessarily work for the longer duration. Hmmm... wondering if I should just get the bucket seat then that is designed to hold up to a 2 yr old. And then buy a FF 5 pt harness booster that can convert to a seat belt booster... Any opinions?

Ideally we like to see kids rear facing to age 3-4, since it is safer and there are so many seats on the market now that can accommodate larger rear facing children. In addition, though there are huge infant seats on the market now, in reality not many 2 year olds are going to be comfortable in an infant seat, even if it is big. So the most economical option is really to get a convertible that will last to age 5-6 and then go straight to a highback booster. Total expenditure (for both seats) can easily be kept to well under $300, whereas a huge infant seat and then a forward facing harness-to- booster is likely to be a MINIMUM of $300, more if you get the quality of harness-to-booster seat that you would be getting with a $300 covertible/booster scenario.

That totally makes sense about why you don't really have seats to pass down... accidents and expirations have a way of helping a seat collection to start over!